dwbf11,
The point is well-taken...for me, just a professional courtesy. I have come up with a rental car hierarchy, so to speak, to address your scenario. If not able to rent the OEMs specific model, then, I'll rent what I believe to be the least offensive to the OEM. Renting from National (and having status) allows that flexibility, as I should be able to get a vehicle from most, if not all, specific OEMs or their corporate family. As you can imagine (and seconded by noah), there are many rivalries/corporate feuds to take into account. To date,, the most challenging has been VW.
Will the dealership kick me out for arriving in a competitors model? I would hope not

, but, there have been multiple occasions when they have commented favorably on my choice in rental cars - which makes a great initial impression.^